Antisera specific for prostatic antigens including acid phosphatase will be raised against normal prostatic tissue and seminal fluid. Polyvalent sera will be used to identify specific antigens in chemically fractionated prostate extracts. Partially purified antigens will be used to raise monospecific antisera which will be further purified by immunoabsorption. Monospecific antisera will be used in immunofluorescent studies and in quantitative gel immunodiffusion stained histochemically to evaluate the persistence, deletion or alteration of prostate specific antigens in primary and metastatic carcinoma of the prostate. The ultimate objective is to devise more accurate means of grading and staging prostatic cancer by immunoassay.